The 870 is a very reliable gun with the Express being a cheaper version than the Wingmaster. Shotguns aren't that complicated and the pump is a reliable platform. You'll find other manufacturers like Winchester, Mossberg or NEF (made in China) often reliable and sometimes cheaper. The popularity of the 870 can have effects on the price.
I would go out and handle as many different guns as you can. Fit will determine if the gun is worth buying.