To be completely honest, despite how awesome the jets are in the Marquis...I thought it looked and felt a little cheezy. I hated the wavy design used for the fill-line, the textured area above the therapy pillar, and the area where the waterfall is located (water intake?) looked cheezy as well. I just didn't like the look of it.
I thought the HS felt like it was built like a tank, and didn't have anything about it that I didn't like...visually. The jets are very good. I didn't like the lounger either, so I decided against the Envoy and Vista. I really liked one seat in the Vanguard that had the rotating jets on my back (not the moto), and really strong jets on my feet. That was my favorite spot in the tub. I like that the cool down seat can act as an easy place to enter the tub. I like the open feel to it. But mainly, I trusted the quality of construction, and loved the dealer.
Also with the Marquis Epic, there was the lounger seat, 1 deep soaker seat, and 2 cool-down seats. Didn't seem nearly as versitile as the Vanguard.
I was tempted to go with the Grandee, but 99% of the time, it will just be me in the tub. So the Vanguard saved me nearly $2k, and will be sufficient for my needs.
All and all, I just thought it felt like it was the highest quailty tub. And looked nice too.