Hi Rodan,
I can't speak to some of the brands out there but there are quite a few that I can. Here's my .02
 
Lynx (I own an Aurora 16) - It's great and clearly it has staying power. I always used mine with either an AES or MADI card so I don't know anything about how it performs via firewire/USB. Drivers have historically been pretty good. For you though, the bad news is that it's only a converter. Lynx doesn't make mic pres (that I know of), so since you said you're looking for something with more pres I'm not sure why anyone is suggesting this.
 
MOTU - The last MOTU I owned was an 896HD...I had it modded by BLA and it's still around in a "straight through" configuration for when I need a few more mic pre's. I've liked my MOTU gear OK...they seem to sound pretty good, but their drivers can be a bit quirky (safety buffers and whatnot...check here for an example but you can search for more: http://forum.cakewalk.com/Rolling-Back-MOTU-Drivers-m1529725.aspx).
 
RME - I own an RME HDSPe MADI fx card. It's only MADI so I can't talk about how RME is regarding conversion or mic pre's, but I hear good things. What I can tell you is that from a driver and support perspective RME is flat out amazing. They fix their drivers when you report legit bugs, their software toolset is fantastic and their onboard mixer/router is the best I've used.
 
Antelope - not sure why this hasn't come up yet. They're a bit high in terms of price, but they sound great (if anyone can tell the difference between my Orion32 and my Lynx they have better ears than I do) and they work. If you're looking for good sound and mic pre's I'd wait a bit and pick up one of the new Zen Studio models. 12 mic pres, DSP fx...what's not to like?
 
Finally, IMO you'd be well served to not worry about the USB vs Firewire stuff. Having used both kinds of interfaces I can't say that there is much difference, and anything past USB 2 has more than enough bandwidth to do as many channels as you need. How do I know? Because my Orion32 is USB2 and does 32in/32out (when I'm not using it via MADI as I usually do). Find the feature set that works for you and worry about connectivity to your computer after.
 
Good luck,
Dean

Many thanks to the group.  Fine information and even "finer" opinions.
 
Dan

Amen Tom. Amen!

Check out the RME vid in my signature for TotalMix. It's way cool!!

It's not a connoisseur's choice, but for a long time, my main interface was a Presonus FP10 (aka Firepod). They're discontinued, but you can pick them up on eBay for about $150 or less. 8 channels, combo line and mic sockets on all 8, integrated (good) DI pre-amps on two channels, straight-through analog output for every channel. Firewire-only. Really low latency, clean as a whistle.
 
I've still got a couple in my mobile recording rig, just used as pre-amps. As others have alluded to above "best" is very expensive. But if you're looking for bang-for-the-buck, no fuss, very flexible, these are worth a look.

Anyone who thinks that a top-notch USB2 audio interface isn't up-to-snuff for professional use is simply wrong. 
The RME units are great performers.  Rock-solid round-trip latency of 4.9ms at a 48-sample ASIO buffer size/44.1k.
There's no Firewire audio interface that bests them (performance wise). 
 
The RME Fireface UFX is a USB2 unit.
30-channels of I/O with good converters.
To do better than that, you're going to spend a lot of cash.
The Lynx Aurora units would be a step up from the UFX (converter wise).
 
Much more important than USB vs. Firewire vs. PCIe is making sure you're getting a proven rock-solid audio interface.
There are great, good, mediocre, and poor units in all formats.
Base your decision on budget, required I/O, round-trip latency, and each unit's performance reputation.
 
RME, Lynx, and MOTU all make good audio interfaces.
Generally speaking, the more you spend, the better the converters and the lower the noise-floor.
 
 

As to Firewire as a standard, I'm loosely in the "it's on the way out" camp. Not on the way out for any good reason, of course. It works great. But it never caught on as a mainstream format, and it's never bedded into the audio world in the same way as (say) ADAT or AES/ABU did. So I expect it to be less and less supported, driver-wise, which is something worth bearing in mind.
 
Luckily, we're all on PC, which is slower about these things. Apple have already dropped it as fast as a hot brick. You can get FW devices working on the new Macs, but it's painful and expensive. And it'll get that way on PC before too long, I think.
 

Jim Roseberry
Anyone who thinks that a top-notch USB2 audio interface isn't up-to-snuff for professional use is simply wrong. 

Quoted for truth. USB2 is, practically speaking, just as fast as Firewire 800.

Jim Roseberry
 
Generally speaking, the more you spend, the better the converters and the lower the noise-floor.
 

This is a very good point (which I realise somewhat contradicts my cheap-and-cheerful Presonus suggestion). But I'd stop worrying about the connection format, and spend more time thinking about the audio components. All of these things *work*, in terms of taking input sources and getting them on your hard drive. Firewire vs USB has no impact on audio quality. But converters and pre-amps do, hugely.

I find it amazing how much Apple (?) has apparently managed to convince people that Firewire is somehow better/more stable for audio recording. Yes, in the beginning days there were more serious interfaces on Firewire, but I have never actually seen anyone have problems with the bandwidth or their USB device, where it recorded or played back fewer channels than quoted. Driver problems and stability, yes, but those exist on both sides and Firewire seems to actually be more particular about the surrounding hardware. Firewire has a higher practical bandwidth than USB2. But USB2.0 still reaches 35 MB per second tops. That translates to 350 tracks at 24 bit, 44.1KHz as a theoretical maximum. Even if you reach a tenth of that it's more than most people record simultaneously. The extra speed of firewire is simply irrelevant in this respect.

The latest RME card actually reaches lower latency on USB than on Firewire if I have to believe them. But once we're in the sub 5ms range for total roundtrip, who cares?

Summarizing, I really wouldn't limit myself to one of the two interfaces, although since you're on PC USB seems the more "universal" choice. It's still very easy to set up a firewire card on your system though, and if you find one with the right features, there's no reason not to take it.