Imperial is a good product, I'd suspect others are good as well. With seed, you truly get what you pay for, and the seed itself is a small part of the cost of planting, compared to ground prep, fertilizer, lime, mowing and possibly spraying. I'm sure everyone who plants on this board will agree!

The plot pictured below is 2/3 Imperial Whitetal clover and 1/3 white dutch clover from the local seed co-op the farmers use.




It is important to keep it mowed, this plot will rarely get over 18" tall, and you do not want it to, because too many plants head out, die back, and lose their vigor. But, you do not need it very tall either. I try to leave it 8" tall going into winter dormancy. Its about 16" tall in the picture where I'm mowing. Try to mow no later than after the feild is 50% "in bloom".

If you insist on a taller greenfield, red clover, or alfalfa, or ablend may be the way to go. Just remember, like any other plant, the larger it is, the more stalky, less palatable, and less desireable it is by deer.