Best Stackable W/D for a rental unit?

[Victor Mondragon]

Fellow Investors, 

I am working on getting my first rental under my belt and am in the process of shopping for a Stackable Washer & Gas Dryer to put into the rental unit.

I am looking for a stackable unit that is low maintenance and hopefully built to last.  I'd love to avoid the 3am phone call about a broken washer or dryer. 

Any makes & models to purchase or avoid would be greatly appreciated!!

Thanks in advance,

Victor