Which Linn Pre-Amp to buy?

I'm in the market for a good used Linn Pre-Amp. I've read and have been told the AV5103 is a better built pre-amp than the Kairn. Also that these units used are sold at a very reasonable price and are not that sought after. Has anyone any thoughts on this?
I owned a Kairn for years and would swear by it for both musical sound quality and versatility in convenience. It has similar sound and attributes as most of Linn line. And as you observed it is a great value. Linn feels that the AV5103 represents a sonic improvement of course, I don't hear it. Cheers!
FWIW the 5103 was Linn's reference 2 channel pre amp at shows until the Klimax Kontrol came out, I still use one and am very happy with it.
I'm Also the owner of a KAIRN and Like R f sayles don't find that the AV 5103 offers that much more of an improvement, and when you consider what a Kairn can be had for used there is no comparison. Regards
I hade 2 Kairn in my audiophile life, uprgading from the original one ( with conventional transformer) to the SPS ( switching power suply) one and was very happy with both of them: musicaly very implicating and good transparency. But I also owne a 5103 for quite a long time and must say that, in my system, it was a much better preamp overall !!! More transparency, more dynamic and, of cours, more music ! Be aware that the kairn is phase inverting and the 5103 is not... but with a good setup, the kairn is no match for a 5103 and you can find one at a very good price now...