[needlespauls]

I personally would not invest $1500-$3000 an everyday run of the mill amp whether new or used. If you plan on holding on to this set-up for life, due to the rig actually not breaking down on you, and because you actually love it, there are better routes to go IMO.

Either spend under a grand and get the best value that you can in a 2x12 combo of some sort. You'll have plenty of power and flexability over the next few years, and if it breaks down, not as big of a deal.

If you do go all-out in the $1800-$3000 range, be very, very carefull in what you buy. AND, I would absolutely buy a half-stack so that down the road you can get different types of heads to add to the cab that you allready have.
AND, I would buy some sort of hand-made boutique offering instead of the every day brand name. Not for snobbery sake, but because they are plain better, and they can last a lifetime. Pure excellent tones, and peace of mind quality.
REEVES (INCREDIBLE alternative to Hiwatt quality and sound, originated by Hiwatt designers
DR. Z (Better Fender type of amps)
SPLAWN (look into these! improved Marshalls etc!!
*would the Landry work for you? yikes imagine the thought of owning this amp?*
An Avatar 4x12 would be great, and a few hundred less than most boutique or common brand names.

As far as more common amps?
Marshall Vintage Modern 50 Watt Half stack
Vox AC30H2 Tube Guitar Combo Amp (Handwired in Britain, 2x12 Celestion Alnico Blue speakers!!!)
Fender 59' Bassman Reissue, Sweet!
The Orange of your choice, of course....

All of these are just my suggestions. If you have a genre or style that you prefer, buy an amp that will be great for that style or genre, but do NOT buy an amp that is totally a one-trick pony. Do you need multiple channels? Do you prefer single channels?

I know that if I had that budget to work with, the amp would be handwired ptp on a turret board, preferably a head and cab configuration, and 30-50watts. All I personally need is a single channel amp that is very very responsive to attack and the guitars controls, and a boost pedal. I'm a knob/pickup didd'ler LOL!
You'de have plenty of clean headroom if needed depending on tube configuration, and you'de have the flexibility of bringing a valve Jr. head to tiny gigs or jams with your cab if you didn't feel like bringing the big-dog. Wow, the amp world is yours bro! Choose wisely!! Don't spend a lot on mediocrity!!! If you do buy mediocrity, spend little, and milk the most out of it, you'll do fine! If you buy High-end, don't pigeon-hole yourself!! Good luck man