I had a pretty shitty experience with tisprings. 4 months and 3 separate deliveries lost in post (apparently) so I gave up, asked for a refund and ordered a Vivid Air from Bike24 that arrived in 2 days (with cheaper post!!)
My friend had the same experience with Ti-Springs.com, the guy kept lying to him about his spring and it took many months before he even shipped it.
It actually became a running joke in our group since the service was so terrible, and after however long, the guy threw in some crappy $2 grips and said something like "I hope my gift more than compensates for the delay".
Also the Ti-Springs.com springs are cheap and heavy - good as a last resort, but better to try and find a quality spring second hand first if you want accurate rates and a much more significant weight saving (The good brands are: Progressive, Obtainium, DSP, Kronos, Manitou, Marzocchi - almost all of these are made by the same OEM, and can even be over-stroked by 0.25" reliably for greater weight savings if desired).
I think the bolts are probably fine though, much easier to source those, and much less complicated to make. It's worth noting this guy makes nothing in house, he just repackages stuff from China and upsells it which is why there's often long waiting times.
The higher quality springs have wider spaced windings (this one is a DSP on an old bike of mine):