Desktop speakers for mixing AND music?

If you haven't already, I would think about where you are going to put them. There are good places to put speakers in a given room related to the room dimensions and it is extrememly unlikely that optimal placement will be on a desk. Been there, done that. So you may end up, for sound quality reasons, with your desk in the middle of the room somewhere...with speakers somewhere between the front of your desk and the front wall, on stands. So factor stands into your budget. Make sure they are the right height. You could also go the "home brew" (or used equipment) route for stands.

You could be making a mistake by buying too small a speaker and deciding to get something bigger later. Also been there, done that (Yamaha HS-5-->Yamaha HS8). It is better to get the right speaker the first time instead of hoping to add a subwoofer later. IMHO the HS8s are fine for casual listening which is how I use mine, in a dedicated listening room the size of a master bedroom. They have more bass and loudness than the HS5s but the HS5s worked pretty good right on my desk, which was up against a wall.

I heard the JBLs in a music store and (like the Tannoys I also auditioned) they seemed to produce a bit too much "self-noise" in my audition, but YMMV.

Other than Yamaha HS Series, I was also going to check out the following, but never got around to it: Mackie MR8mk3, Event 20/20BAS.

The Tannoys I referred to in my post above were the 502s, which I bought and returned the next day, due to "self noise". At the time I had them on my computer desk listening nearfield and found this distracting during quiet passages, in spite of them otherwise sounding excellent for their size.

I just had the Tannoys and then the HS5s temporarily on the desktop. About a foot from the wall behind them, which is not correct positioning. I guess you could say that the small Tannoys, except for their self-noise, sounded a bit smoother than the HS5s when both were not set up properly. Not sure which would sound better if they had been set up properly. Any self-noise might be bothersome from a 3 foot listening distance but not be a factor at all from a 6 foot distance.

My audio system was in the same room and my Magnepan 1.7s stood in the optimal speaker locations in the room. I never tried the HS5s in the same spot the Magnepans were. When the Maggies needed to be sent out for repair, I got this crazy idea about combining both my computer system (HS5s) and my regular stereo system (Magnepan) into one system. So I traded in the HS5s and put the new HS8s on sand-filled 4-post Target stands roughly where the Maggies were, rather than on the desktop. Now all is good.

Like I said in my first response, you won't get optimal sound with studio monitors if you stick them on your desktop (or be able to tell their capabilities in a music store). Like audiophile speakers, time needs to be spent finding the best positioning for them, the room needs to be treated and they have to be sitting on good stands at the correct height and you need to feed them good source material. Of course most studio monitors have switches on the back to help compensate for less than ideal positioning, but this should only be done as a last resort.

You need to get some of these home and try them out, on good stands with lots of time on your hands, bringing back to the store the pair that doesn't sound as good to you in your room the way you have it set up. Room differences, positioning differences, personal tastes, loudness levels, etc. can obfuscate the differences between different sets of monitors.

Kudos to Tannoy for looking after this quickly. They are good guys in my books.