I have collected quite a few sopranos and have excellent examples of many vintage types. I have one Saxello and was sold it by someone who has owned and played many. The one was I bought was supposedly above average in intonation, yet it has probably the dodgiest intonation of my entire collection. The ergonomics are also not that great. However, these are very collectible horns and excellent, complete and undamaged examples in silver plate are selling in the USD 3,500 to 4,000 range.
I also own Buescher tipbell sopranos from the same time period and they seem far superior in every way. The intonation of the oldest model (1926) I have is particularly excellent and it is relatively easy to get the palm keys to speak. The only vintage horns I like as much are a straight Buescher True Tone from the same year and a straight Conn gold plate "Chu" from 1927. When I am travelling and need a horn to play, I almost always grab the straight Buescher True Tone - occasionally the Tipbell or the Conn and never the Saxello. I almost hate to admit it, but another favourite is an early Yamaha YSS-62. A really nice horn with no real quirks and great intonation. So personally, I wouldn't buy a Saxello to play, but I think any good collection should include one.