Questions before I buy a Solo II

But I have a couple questions I couldn’t find answers for

For one, how long does one “bowl” or pack last?? And (I know this is a bad way to ask) but like how high does it get you. It just seems like on all these dry herb vapes you’re putting such a small amount of weed in the chamber! I know it uses the thc like wayyyyy more efficiently but as a pretty heavy daily smoker I just can’t imagine that amount of flower possibly satisfying me and it seems like it’d be annoying to constantly be repacking?

Also I have seen people say to vape it until the weed is like a brownish color, but when ur smoking a bowl, you keep going until it’s all ash. Now I’m assuming that the vape burns at a lower temp so it can’t fully turn the flower into ash but could I take my “used” brown flower and throw it in my bong for another hit?

Lastly, the biggest reason I’d purchase is (mainly the price and) because it’s supposed to use bud so much more efficiently (I go through an oz every 2-3 weeks normally) and I was hoping that this would help my weed last longer and thus spend less money long term. I’ve seen some stuff on that, but can someone who owns one of these products personally speak to how much weed/money it saved you?