I have found in the past from using both MH and HPS that the results are similar. You should notice tighter bud formation and a little more crystal production with a MH. With an HPS I found the buds got larger, but not quite as dense. Also, crystal production didn't seem to be quite as much as the MH produced.

About 2 years ago I have done a side by side grow using both the HPS and MH and have noticed those results. The clones were all from the same mother. Even though there was a difference - I wouldn't say it was large enough to really make a choice. They both seemed the same potency and the weights were very similar. Just the bud density is what I noticed to be most prevalent. Hope this helps.

TGT