Momentum M-series reviews?

Winnebago completed the purchase of GD in November of 2016, but as of yet you won't find any Winnebago mention on the GD website or vice-versa. I can't say I've read much worse after the purchase than before. For the most part GD seems to maintain a good reputation as had Winnebago.

I have read that Grand Designs was purchased by Winnebago.

Grand Design was attempting to be a step above the rest and build quality. They were one of the extremely small number of RV manufacturers that actually built and operated a quality control inspection department. Alas, earlier this year they sold out to Winnebago. Quality of current and future product is unknown.

They're all the same; built very quickly and shoved out the door to be sold. Pick out the floor plan you like and go with it. Be prepared to visit the dealer for warranty repairs. My recommendation is to not buy new. Get one lightly used that has had the bugs worked out.