Depends on how much of the Moon you want to suck down at once and how good your seeing can be.
The 290 will show you finer details if the conditions permit, but will show you only about 1/4 the area at a time.
By the same token, the 5.86 micron pixels of the 174 would gather light more optimally at around f/25, so you'd probably want to be using a barlow/powermate anyhow.
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