Need Help. Lag Screw vs. Carriage Bolt

felt like through bolts would be better, but you never know...sort of like how surprised I always am at how strong "just glue" is. However, being in cedar and being taken out and put back in so many times, I think the threads are on their last bit of bite (say that 3 times  ). I'll PROBABLY go with stainless for BOTH reasons you guys pointed out...
1) it does resist corrosion better
AND
2) my kids will outgrow this set in 4-5 years. If I upgrade the structural hardware to stainless, I'll use it as a selling point when I need to sell this one and get the "super-duper-mansion model".

The good thing is that the only exposed part of the bolt will be the rounded bolt head. The nut on the other end will be recessed into the wood. I'm also a little surprised that this isn't standard construction on this type of playground system...you would think that for the

$3600

() they're charging for this thing AND that it will be used by kids, they would go all out on the hardware (I got mine for a steal at $1200 and still felt like I paid too much for a swingset...but what are you gonna do when a 4 year-old angel says "Daddy...pleeeeeeeeeeze"  ). You can see from the picture below (from Rainbow's website) that the entire deck is supported by a gambrel-like "bent-leg" support system. This has to put a great deal of force on that joint. Again, this is intuitive on my part and a stress test could prove me wrong, but it seems that at that angle the joint WANTS to fail. I mean, would any of us build a dining table like that and expect it hold up over years of use? So, bolts...definintely better. Now...maybe I need to fabricate a steel truss support for that joint...

Any other "no-brainer" upgrades you guys would recommend?

Thanks. Ilike through bolts would be better, but you never know...sort of like how surprised I always am at how strong "just glue" is. However, being in cedar and being taken out and put back in so many times, I think the threads are on their last bit of bite (say that 3 times). I'llgo with stainless forreasons you guys pointed out...1) it does resist corrosion betterAND2) my kidsoutgrow this set in 4-5 years. If I upgrade the structural hardware to stainless, I'll use it as a selling point when I need to sell this one and get the "super-duper-mansion model".The good thing is that the only exposed part of the bolt will be the rounded bolt head. The nut on the other end will be recessed into the wood. I'm also a little surprised that this isn't standard construction on this type of playground system...you would think that for the) they're charging for this thing AND that it will be used by kids, they would go all out on the hardware (I got mine for a steal at $1200 and still felt like I paid too much for a swingset...but what are you gonna do when a 4 year-old angel says "Daddy...pleeeeeeeeeeze"). You can see from the picture below (from Rainbow's website) that the entire deck is supported by a gambrel-like "bent-leg" support system. This has to put a great deal of force on that joint. Again, this is intuitive on my part and a stress test could prove me wrong, but it seems that at that angle the joint WANTS to fail. I mean, would any of us build a dining table like that and expect it hold up over years of use? So, bolts...definintely better. Now...maybe I need to fabricate a steel truss support for that joint...Any other "no-brainer" upgrades you guys would recommend?