I have positive things to say too.
My first basset hound I had spayed at an early age, way before her first season and she sailed through it as though nothing had been done.
My second, I got on from Basset Hound welfare on her first birthday and had her spayed straight away. She was a little sore, and made the most of it for a few days but other than that is wonderful.
Even though they are basset hounds, neither have had a weight problem (unlike their owner!! lol), so IMO I don't think spaying should be a problem at all.