Hi Ron - Welcome to the forum.

There are several turntables in that range that offer excellent performance. I haven't heard the Denon, so, I have no point of reference, but, will share this, for what it's worth: Several years back, I picked up an old 1960 AR XA belt drive turntable (with a crappy fixed headshell) and did a few minor mods to it (RCA jacks and a bit of dampening.) It outperformed my direct drive Technics SL-D202 by a wide margin. The noise floor was significantly reduced, and the music had better rhythm. I was very surprised. These days, I use a VPI, but, that purchase of the vintage XA opened my eyes to the benefits of belt drives.

How much improvement you are able to hear might depend on the phono stage in your system, and how much it can reveal. If you're not listening to vinyl all that much, it might not be worth going for the turntable upgrade -- I'm all for people getting deeper into analogue, but, if that 600 bucks can be put towards a DVD player that you'll get much more usage out of, I'd say, that's a wiser place to put your investment. If you can audition a turntable in your system, that would be best. Only you can determine what works for you. Who knows? You might find the improvement is significant enough that you make the time to spin discs.

If you do not sit and listen to music but rathr use it as filler, there isn't much point in buying a better table. Wait until the system has improved and you have time to enjoy your purchase. In the interim spend a few dollars on improving the support for the table and providing the best isolation from external interference.

I presume what you mean when you say, "...it's just that I don't get to sit and listen as often as I would like (my system is in one room as part of a home theater setup)", is that you defer to use of the HT setup by other family members for TV viewing etc. If that is the case, and the new DVD player would please others as well as yourself, you're probably going to go that way, and understandably so.

As for the superiority of modestly priced belt drive TT's to your present table, there's no doubt about it, Ron. When the budget and the general happiness justify it, go for one. There are several good ones out there between $500-$1000. When you're ready to buy, come back and we'll all haggle about which one is the best.

Incidentally, how long have you had those Onix speakers and what do you think of them?