For me, 1103p is the bulldozer of rootstocks it overcomes every obstacle you put in front of it it’s a workhorse alongside St George pretty bulletproof and 1103p is resistant to sharpshooters as well. I will add that overall the vines on SO4 have been more productive but that is expected as SO4 is super vigorous for the first 30 years of its life then slows a bit which is fine. It’s been a really good rootstock for Sauvignon Blanc and works good for Pinot as well. I also have 5BB kober for Malbec it’s a good rootstock when it’s not behaving weird it will produce good growth and my Malbec with produce great one year then low the next or might just produce vegetation without grapes it’s like the rootstock has multiple personality disorder sometimes kinda Russian roulette on what kind of year your going to have. But on a good year I’ll get Malbec with big fat clusters and brix up to 28 it’s crazy.
I also tried out riparia gloire only because I wanted to grow Carmenere as well as I like trying less common varietals out and that’s all I could obtain it on from the nursery that year and it has performed good better than expected vigorous and doesn’t seem to mind acidic salty soil.
The rootstock that the nursery put half my grapes on because they thought it would work at my location was a big failure, 101-14 I lost all but 3 vines planted on it had to replant 80% of my vineyard because of it they paid for it though. Went with SO4 and 1103p for everything afterwards. Out of the 3 surviving vines on 101-14 1 is the biggest best performing grapevine in my vineyard the singular surviving Fiano vine.
I also put in some blaufrankisch on a whim because I guessed it would do well here and am the only grower in the area I planted that on 3309c which is working out as well. Have narrowed it down to most rootstocks work well here but 101-14 1616c and 420a are bad picks.