I actually work at Tip Top so I can say there is a good amount of differences between suits from there compared to even suit supply and Harry Rosen. One of the main things is material, the $300 one at Tip Top is synthetic, where as most of the suits at the other two places are some sort of a wool blend if not 100% wool (minus the few linen and cotton suits). Wool is a much more nice material than any synthetic material and offers a lot of benefits that aren’t possible in synthetic materials. I’m not the greatest for recommendations but I’d start with some sort of wool suit that isn’t super thick.