Finally the weather got warmer so I had my first 7km lake trial on my new Race 14'x25'' custom glass carbon. Last year I was paddling Falcon 12'6''x27,25'' race carbon and a year before NSP 14'x28'' touring SUP.
The conditions on lake Bohinj were far from perfect. It was windy, and waves were quite big for lake this size -up to 30cm.
Stability - out of 3 SUP I had in the past this is the less stable, but its also the narrowest. For the first paddle since October last year and not much physical activity in winter months I am very satisfied, specially secondary stability. I had some dificulty paddlig side wind/waves but with speed and nose tracking it was good. I used the standar finn it came with the board. I will try FCS C4 Spitfire to see if any change.
Tracking - I was amazed with tracking, specially upwind as nose was cutting the waves easly and with no vibrations, which was really confortable. Downwing was really nice as I was picking those small waves and I did not even move my feet (i was trying hard not to fall in the water as its still pretty cold) actually on the mountin right next to a lake there's still skiing season in the ski center - www.vogel.si/winter
Speed - it feels fast, but with not perfect flat conditifons and no mileage since october I cannot tell much. I had my Garmin watch:
connect.garmin.com/activity/742556285

I consider my self as recreational paddler with 5-6races in the summer ( I did finished 28km lake race in 3h36min last year) and this is just my '5cents' as I have new SUP and happy. :-)

Tomorrow I will have my first Adriatic sea paddle...

Keep SUPping, and cheers from Slovenia!