KChau

Hello all, I am new to golfing in general and wanted to invest in a decent set of golf irons over my current set. I have an older set of Mizuno irons that I got handed down to me, but the grooves are pretty gone and are a little rusted. I wanted to try these Katanas because I found a good deal on them and think they may be beneficial to have. Plus I love the look of them! I do not know my swing speed at this time, but I am concerned that it may not be worth my money because it is a SR flex iron. I am 27 and average build and my thought is that I can get my swing speed up to average with practice. I do plan to practice more and get my swinging more consistent and wanted to reserve these irons for the golf course and occasional practice rounds once I get better. The other justification I thought about was that my girlfriend can use the golf clubs as her swing speed is very slow at this time. I informed the seller I needed more time to think about getting an SR flex, but he also informed me that Japanese SR flex is equivalent to US R flex. I haven't been able to find this information online anywhere and I think the golf clubs were made in 2013. They look like they are in really good condition and are regripped, but I'm unsure if the shaft itself will fail over time due to age. There is not much information out there for these golf clubs, nor shafting difference between US and JDM markets, so I am open to hearing everybody's opinion on whether or not it would be worthwhile to get it as well as if his claim about the JDM SR flex = US R flex is true. Thanks in advance!