I have Bridger, Desert Sunrise and Top Keeper winter onions and they are all bulbing now (37 degree latitude). The plants were covered with a row cover tunnel through winter and did really well. I had a few bolted plants in the Top Keepers and one or two in Desert Sunrise, none in Bridger. We had a wind storm this week that knocked over some plants, but for the most part they are still upright. I love these onions!

Great to hear yours are doing well also Planatus. Any pics to post?

I tried every type I could find this year including all three you list, plus my favorite T420 from Takii. The top keepers I might not grow again as they are a little smaller and are more prone to mildew trouble.
Desert sunrise are amazing fresh market onions but one patch I transplanted earlier all bolted. The other patch is doing great. I have to really get the timing down on that one.

This is only my second year working with these onions, and after a cold wet spring, they are maturing two weeks later than last year. Pictured are Desert Sunrise (left), Top Keeper (right) and Bridger (rear).

Since the storm last week many plants are showing new upright leaves, so I have them propped up a bit so they can finish off naturally during the dry week ahead. Bridger looks to be about a week behind the other varieties, but very vigorous with no bolted plants.

The best planting dates here are the first week of August, so these winter onions are coming in right at 300 days, but still way easy to grow and 7 weeks ahead of our earliest bulb onions. Since ours is a serious food garden, it's great to have onions to fill the early summer gap, after spring multipliers and winter leeks, but before the new crop of bulb onions from seed.

Wondering if you have tried the Keepsake variety, which did very well in the UMass trials.

Here is a link that might be useful: UMASS Overwintered Onion trial

I pulled these a week ago and could not be more pleased at how they are curing under the wood shed. The yellow onions are mostly Bridger with a few large Top Keepers, and the red ones are Desert Sunrise.

Hey those look great! I missed the post about Keepsake, and no I haven't tried them. Any idea who sells seed?

My onions have all been knocked down and are field curing for another few days. I'll try to post some pictures by the weekend.

-Mark