To be honest, I think they’re both great. I’m partial to Humminbird myself, probably because I have more experience with their higher-end units.
As for the Lakemaster chips, they’re pricey but very useful on lakes with a lot of nooks and crannies. On the sandy bowl-shape lakes, they don’t show much because there’s not much to show! There are some decent deals for them on eBay.
I caught my personal best smallie, 6-8, this season just a week after getting the chip. It alerted me to a little (10′) point extending from a reef that I was previously unaware of. I don’t think I’d have found that spot (or the fish) without the chip.
Also, don’t forget about the Navionics charting app if you have a smartphone. It costs about $10 to start with a small annual renewal fee. That’s what I use for ice fishing. Well worth it.