No. It's poor engineering choice on APC's side to make a UPS without vents. Dust being dust, still gets inside and makes cooling even harder. Quality of the battery is secondary. It would last longer in generic ups.
Dust or no dust, it's still a bad idea to mount batteries on their sides. Is there any other appliance that has mounted its acid containing battery on the side? Why don't vehicles have their batteries on their sides. Seems like a cool idea.
My APC is a culmination of all retard engineering choices one could make. The list is long.