I haven't seen a $30 battery in my area in at least 10 years. The last crappy wet cells I bought from Autozone, Advance Auto and NAPA have been just shy of $50 and that's after the core return. The "good" ones make it two seasons and that's with using battery tenders during the winter.
All the YUASA sealed batteries I've owned have gone 5 years and get replaced because they are starting to slow down, never a catastrophic failure like wet cells.
I switched over to the AGM batteries a few years ago. My Hayabusa's Motobatt battery is on its 3rd year. I live in northern Indiana, park the bike in November and start it again in April. I don't even bother putting a charger on it.
I do the same with the Motobatt in the 500T except disconnect a terminal due to the hefty power drain of the VFD clock.
Those batteries ran me $50 and $65 SHIPPED off ebay and have 2 year warranties. The junk wet cells typically have 90 day warranties. I'll gladly pay $5 to $15 more for a battery that I don't have to dick around with charging in the winter and can start a Triton V10 engine 50 times in a row.
My 650T is in need of a new battery this spring but unfortunately the Motobatts in our size are on back order from the dealer that sells them at a reasonable price.
I ended up buying a different brand AGM by UPG/Adventure Power for $48 SHIPPED off ebay. I don't expect it to be as good as a Motobatt but it'll still be 10X better than a wet cell.
Oh, several years ago the wet cell in my mint 500T pissed acid onto the side panel lock which caused several hours of hell getting the lock to release and then cleaned up and operating again. Another great reason to go with a sealed battery.
What I don't understand is why wet cells became history for cars in the late 70s yet that dinosaur technology is about all I can find locally for motorcycles.