If you have the budget, check out Equator at http://www.equatoraudio.com/   I use their D5s with a Tannoy sub. Awesome sound. Have made a HUGE difference in my mixes.

bitflipper
Agreed that 8" is the ideal woofer size if you don't have a separate subwoofer. Anything smaller is going to leave unheard mysteries in the low end.
 
However, there are advantages to using smaller speakers with a separate sub. During mixing, it actually helps to remove the extreme low end so you can concentrate on the vastly more-important (regardless of genre) midrange. Most subs come with footswitches so you can easily switch them in and out. In terms of cost, the sub's going to run you between $400 and $1200, but stepping up to the next tier of monitors is going to be an even greater increase. And you have the option of buying the main speakers now and adding the sub later.

How come Focal's sub6 is $1850?  I mean it's a single speaker and a cab....for $1800??

then there are the Yamaha HS8... but the JBL's are cheaper in price.  I think Sweetwater is also offering 1/2 off for the 2nd speaker thru March.
 

dang.... sale over...and was going to get some JBL's

So much advice...

More advice:

Listen before you buy.  Don't just rely on recommendations.

mixmkr
 
How come Focal's sub6 is $1850?  I mean it's a single speaker and a cab....for $1800??

A single speaker that only has to handle a single octave!
 
Focals are freakin' awesome speakers, but IMO overpriced. 
 
Subwoofers generally are going to be pricier because they have to be heavier and much more solid construction, and there's a lot more metal in them. The high-end ones also use manmade high-tech materials for the driver rather than coated paper. The combination of solid construction, high mass and super-stiff, super-light cones means less IM distortion and ringing - but at a cost.
 
Still, I get by with a $400 M-Audio paper-cone sub that rings a little worse and has poorer IM distortion numbers than the expensive models, but is flat. And anyway, my room contributes far more inconsistencies down there than the speaker ever could.

Scoot
Do you know about Thomann
http://www.thomann.de/gb/...ld_monitors&oa=pra

Yeah I get nearly all my stuff from there, Great online shop!
 
I know listening to monitors before buying is essential but I'm in Ireland  (and the countryside at that) so not really spoiled for choice here for the types of big shops that stock this gear.
 
The few I visited hadn't much more than a token set of Yamaha's & KrK's. Even most of the online shops selling in Ireland are shipping from the UK. 
 
Iv'e taken the plunge and ordered the LSR 308's. I'll report back how it goes, I feel like a kid waiting for Christmas :-)

Matt
So much advice.... don't over think it.  Get the LSR308s.  I personally 100% guarantee you will love them.

So I took delivery of my 308's today and your right Matt, I LOVE them!
 
I actually took the day off work to make sure I didn't miss the delivery, My initial enthusiasm was dampened a bit when everything I listened to through them seemed very thin on the low end, Even tracks that I know have serious low end when heard out but boosted the low frequencies using the switches at the back and I was very relieved, Not sure if my room acoustics can account for this?
 
Anyway I can hear elements I never heard before in tracks I thought I knew very well. this explains why anything I have "produced" in the last couple of years using a set of creative labs 2" speakers sounds  like complete sh1te when I listen on another system.
 
thanks for all the advise guys, Now I'm off to the batcave for the weekend 

You said some helpful things in that post, mondaydave.
 
I'm glad you are pleased with your purchase.