New trailer tires needed, exploring options

bass2reds

Weapon of bass destruction
Joined
Jul 24, 2013
Location
Plantation, Florida, United States
#1
My trailer has galvanized rims with no rust but the tires are 10 years old. The tread is almost like new due to low mileage and it is garage kept but I'm getting nervous about the few long trips I take each year.
I'd like to replace the tires and have been looking at ads for the Maxxis M8008 ST Radials. I currently have Bias Plys now. Has anyone used these and what was your experience?

My options are to just replace what I have now with 2 more Bias Ply tires.
Replace with the Maxxis Radials. Both options 1 and 2 require jacking up my boat while I get the new tires mounted and then putting the wheels back on.
Or sell my existing rims with the old tires since they still look great and just buy two new Rim & tire combinations at about $130 each and swap them out, possibly making 1/2 my money back when I sell the old ones in the classifieds.