1) I used a Denon 103R with my Cornet. Needed a step-up, used the Lundahls. 1:20 was too hot, 1:10 worked fine, so I would start there
2) The Lundahls are fine transformers for the money, and I would recomend them for those on a budge. If you have more cash available, the Stevens and Billington trannies are in a whole other leauge (but cost four times as much.) That's what I used now. Also, David Slagel here in NYC handmakes his own step-ups, and supposedly they best the S and Bs! Will have to try them at some point soon.
If you are watching cash, the Lundahls are pretty darn good, though.