Integrated Tube Amplifier for First Timer?

Alot of great choices. The Onix SP3 is an excellent integrated but it is not as detailed as say the VTL. I would choose an integrated that is hardwired and get a schematic for it. With the horns you have to make sure you don't get a bright sounding integrated. An old hi fi guy once told me to buy the tube amp with the biggest heavist iron (transformers). That puts the Onix in a league of it's own weighing in over 50 lbs.
I want to hear the new Melody SP7 (same as the Onix but replaces the SP3) featuring EL 34's. If it in fact does have better detail than the SP3 then it will be a killer integrated. Just the EL34's alone gives you some of the best midrange in the world. I have heard the Cayin and it sounds great on Renyards. I like the fact that you can run it in Class A. I can't say I actually heard a differnce though and I have only heard the EL 34 versions of it.
I would also check out Upscale Audio for their integrated amp primaluna. Based on Cost I'd chose the Melody SP7 or Onix's version of it.

Soundquest SQ 88 55wpc ,auto bias, very nice sounding

You know, I'm going to start sounding like a broken record here on these boards, but one of the few truly affordable tube integrated amplifiers that "make the grade" are from Vista Audio. Maybe its that Serbian luv', but these things sound like what a good tube amp should be - top to bottom balance, harmonically rich but not overly warm, great extension, detail, dynamics, >/insert adjective here. From the looks of your requirements, the i34 should meet em.

That said, there are plenty of goodies I have not come across in my travels. The bulk of units I've compared it to have been; Rogue, Anthem, Jolida, ASL, Prima Luna, Dynakit, and Onix. As always, its about synergy and personal taste. A 60 day trial period however makes things pretty risk free.

Whatever you decide on - good luck!

Rogue Cronus is a great choice! Excellent quality and the customer service is superb!!

try a prima luna dialogue one , 36 watts but large transformers(weighs around 65 lbs give it much more power. my speakers are only rated 86 db but can play very loudly in a medium sized room