Yeah, as long as the plastic inside is in good shape, the box condition is negligible. Unless you are a collector or something.
Heads up... this is the old tool Eduard 190. Not exactly old as it was released in 2006 but for whatever reason(s), Eduard released a completely re-tooled set of 190's starting in 2017. From what I remember, there were some accuracy issues with the 2006 release as well as difficulty in assembly with all of separate panels.
Also... Eduard has released a comprehensive set of 190 sub-types with both releases. If you are interested in doing the A-8/R-2, there is an old tool and new tool kit with the specific modifications included.
2007 Kit #8175
2019 Kit #82145
You may have the armored glass pieces but not the fuselage armor, since the A-8/R-2 included the fuselage armor as part of a brand new fuselage.
Recommendation from someone who has tried to convert a Ta152H-1 into an H-0, if there is an available kit that offers you the sub-type you want to do, TAKE IT!