I have not tried both the tsx and the mrx in the same gun,so I have no direct comparison.However,both of my 7mmstw rifles average 1/2" with the 140gr ballistic tip.The groups did tighten up slightly as I increased the powder charge,so the mrx may match the ballistic tip in one rifle once the fine tuning is done.I am going to try increasing the powder charge one more grain on my next range session.The 180gr tsx averages 5/8" in my 300ultramags,while the 180gr ballistic tips average 1/2",so in all cases the tsx and mrx are very close to being the most accurate bullet in all of my rifles.